Vibrating Wire Total Pressure Cell is installed between retaining wall and soil and then monitor total earth pressure caused by loads of surrounding grounds. 
Once the total pressure of the cylinder cell is given or load of the surrounding grounds is added, 
the fluid which fills the inside of the cylinder cell gets pressure and this pressure is delivered to the sensor. 
At this time, once pressure is given to the diaphragm of pressure sensor, tension of vibrating steel wire is changed 
then plucking coil senses the frequency of the changes. Once the primary coil generates a frequency signal on the vibrating wire, then the secondary coil sends the frequency to a measuring instrument. 
The measured frequency is converted into pressure through calibration factors.